java实现后台自动发邮件功能

java后台自动发邮件功能怎样实现呢?下面是小编带来的解决方法，希望对您有所帮助!

文件

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "_2_">

<web-app>

<servlet>

<servlet-name>mailsenderservlet</servlet-name><!--邮件发送程序-->

<servlet-class>SenderServlet</servlet-class>

<init-param>

<param-name>server</param-name><!--邮件服务器SMTP地址-->

<param-value></param-value>

</init-param>

<init-param>

<param-name>port</param-name><!--邮件服务器SMTP端口-->

<param-value>25</param-value>

</init-param>

<init-param>

<param-name>address</param-name><!--邮件地址-->

</param-value>

</init-param>

<init-param>

<param-name>username</param-name><!--邮件账号-->

<param-value>username</param-value>

</init-param>

<init-param>

<param-name>password</param-name><!--密码-->

<param-value>******</param-value>

</init-param>

<init-param>

<param-name>validate</param-name><!--SMTP服务器是否要求验证-->

<param-value>true</param-value>

</init-param>

<init-param>

<param-name>time</param-name><!--扫描数据库时间间隔（分钟）-->

<param-value>5</param-value>

</init-param>

<load-on-startup>1</load-on-startup>

</servlet>

</web-app>

servlet:

package l;

import let.*;

import .*;

import .*;

public class MailSenderServlet

extends HttpServlet {

private MailSender sender;

private Thread t;

public void init() throws ServletException {

sender = new MailSender();

oot(root);

String server = getInitParameter("server");

String port = getInitParameter("port");

String address = getInitParameter("address");

String username = getInitParameter("username");

String password = getInitParameter("password");

if (server == null || port == null || address == null || username == null ||

password == null) {

tln("系统文件错误：邮件发送程序初始化失败！");

return;

}

erver(server);

ort(port);

ddress(address);

sername(username);

assword(password);

String time = getInitParameter("time");

if (time != null) {

ime(eInt(time));

}

String validate = getInitParameter("validate");

if (validate != null) {

alidate(eOf(validate)eanValue());

}

t = new Thread(sender);

t(); //启动邮件发送线程

}

public void destroy() {

(); //停止邮件发送线程

try {

(1000);

if (ive()) {

tln("邮件发送线程未停止。");

}

}

catch (Exception e) {}

}

}

邮件发送程序

package l;

import .*;

import .*;

import .*;

import ;

import vation.*;

import .*;

import age.*;

import rnet.*;

/**

* <p>Copyright: Copyright (c) 2004</p>

* @author

* @version 1.0

*/

public class MailSender

implements Runnable {

private int time = 5 * 60 * 1000; //扫描数据库时间间隔

private boolean flag = true; //停止线程标记

private String server = ""; //SMTP服务器地址

private String port = "25"; //SMTP服务器端口

private String address; //用于发送EMAIL的发送者地址

private String username; //发送者的用户名

private String password; //发送者的密码

private boolean validate = true; //邮件服务器是否要求验证

private File root = null; //WEB根目录

MailConfigManager manager = nstance();

public MailSender() {

}

public void setAddress(String address) {

ess = address;

}

public void setPassword(String password) {

word = password;

}

public void setPort(String port) {

if (port != null && th() > 0) {

= port;

}

}

public void setServer(String server) {

er = server;

}

public void setUsername(String username) {

name = username;

}

public void setValidate(boolean validate) {

date = validate;

}

public void setTime(int minute) {

= minute * 60 * 1000;

}

public void run() {

long lastTime = new Date()ime(); //保存前一次发送邮件的时间

while (flag) { //服务器停止时退出线程

long k = new Date()ime() - lastTime;

if (k < -1000) { //防止系统修改时间

lastTime = new Date()ime();

continue;

}

if (k > time) { //超过设定时间间隔开始发送邮件

sendData();

lastTime = new Date()ime();

}

try {

p(100);

}

catch (Exception e) {}

}

}

public void stop() {

flag = false;

}

/**

* 检索数据库，并发送邮件

*/

private void sendData() {

ResultSet rs=null;//读取数据库数据

try {

Session session = nstance(getProperties(), new Authentic());

while(flag) {//服务器停止时退出线程

String toAddress = null;//发送地址（从rs中得到）

String subject = null;//邮件主题

String content = null ;//邮件内容

String file[] = null;//所有附件（绝对路径）

sendMail(session, toAddress, subject, content, file);//发送邮件

}

}

catch (Exception e) {

tStackTrace();

}

finally {

if(rs!=null){

try{

e();

}

catch(SQLException e){}

}

}

}

/**

* 发送邮件

* @param session 会话

* @param toAddress 目的`地址

* @param subject 邮件主题

* @param content 邮件内容（HTML）

* @param files 邮件附件

* @return 是否发送成功

*/

private boolean sendMail(Session session, String toAddress, String subject,

String content, String[] files) {

toAddress = ";

try {

Message rs = new MimeMessage(session);

Address from = new InternetAddress(address);

rom(from); //发送地址

ecipient(, new InternetAddress(toAddress)); //接收地址

ubject(subject); //邮件主题

Multipart mp = new MimeMultipart();

BodyPart html = new MimeBodyPart();

ontent(content, "text/html; charset=GBK"); //邮件HTML内容

odyPart(html);

if (files != null && th > 0) { //邮件附件

for (int i = 0; i < th; i++) {

MimeBodyPart mbp = new MimeBodyPart();

FileDataSource fds = new FileDataSource(files[i]);

ataHandler(new DataHandler(fds));

ileName(deWord(files[i]), "GBK", null));

odyPart(mbp);

}

}

ontent(mp); //邮件全部内容

entDate(new Date()); //发送时间

(rs); //发送

return true;

}

catch (Exception e) {

tStackTrace();

return false;

}

}

/**

* 邮件会话属性

* @return 会话属性

*/

private Properties getProperties() {

Properties rs = new Properties();

("", server);

("", port);

("", validate ? "true" : "false");

return rs;

}

public void setRoot(File root) {

= root;

}

class Authentic

extends Authenticator { //验证密码

public Authentic() {

}

public PasswordAuthentication getPasswordAuthentication() {

return new PasswordAuthentication(username, password);

}

}

}

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